WEBVTT A FREIGHT TRAIN DERAILED LEAVING CARS WITH HAZARDOUS MATERIAL DANGLING OVER A RIVER, THIS IS BACK IN JUNE. TODAY EMERGENCY RESPONDERS LEARNED WHAT TO DO WHEN THAT HAPPENS. PITTSBURGH ACTION NEWS 4 INVESTIGATOR PAUL VAN OSDOL WAS THERE. Reporter: TANK CARS LIKE THIS ONE CARRIED BILLIONS OF GALLONS OF CRUDE OIL EVERY YEAR, SOME OF IT THROUGH THE PITTSBURGH AREA. BUT RECENTLY THERE HAVE BEEN SEVERAL HIGH-PROFILE DERAILMENTS, INCLUDING THOSE RIGHT HERE IN WESTERN PENNSYLVANIA. EMERGENCY RESPONDERS CAME TO THIS RAIL YARD ARE DECIDING WHAT TO DO WHEN THESE CARS GO OFF THE TRACKS. IN FEBRUARY SEVERAL THOUSANDS GALLONS OF CRUDE OIL. TANK CARS WERE DANGLING FROM A BRIDGE FOLLOWING ANOTHER DERAILMENT. NORFOLK SOUTHERN SAID THE PUBLIC SHOULD NOT BE WORRIED. HAZARDOUS MATERIALS MOVING IN TANK CARS IN THE UNITED STATES MAKE IT FROM ORIGIN TO DESTINATION AT A RATE OF 99.98%. Reporter: YET AT THIS TRAINING SESSION, A RAILROAD SAFETY EXPERT ACKNOWLEDGED ACCIDENTS DO HAPPEN. THAT'S THE BIGGEST SOURCE OF LEAK ON TANK CARS. WHY? THAT BIG GASKET IN THERE, THEY DON'T MAINTAIN IT. Reporter: THE FEDS CALLED FOR TOUGHER STANDARDS FOR AGING TANK CARS, WHICH ONE RAIL EXPERT CALLS PEPSI CANS ON WHEELS. SENATOR BOB CASEY SAID THE GOVERNMENT NEEDS TO DO EVEN MORE. I GET VERY CONCERNED ABOUT IT. WE'VE GOT TO MAKE SURE THAT SAFETY PRECAUTIONS ARE ADHERED TO AND THAT THERE'S AS MUCH PUBLIC NOTICE AND INFORMATION AVAILABLE. Reporter: BUT THE RAILROADS DO NOT REVEAL SHIPPING ROUTES OF CRUDE OIL OR OTHER HAZARDOUS MATERIALS. WHY CAN'T YOU TELL US HOW MUCH OIL IS BEING SHIPPED THROUGH DOWNTOWN PITTSBURGH? WHAT THE FEDS HAD ASKED FOR IS THAT WE RELEASE THAT INFORMATION TO WHAT IS KNOWN AS THE STATE EMERGENCY RESPONSE CENTER. Reporter: BUT THE STATE WON'T RELEASE IT EITHER. BECAUSE THE RAILROAD SAYS IT'S PROPRIETARY INFORMATION.